ANTHRO 105 Exam 2 - Stage 1: Evolution and Inheritance

18 review-sheet terms. Read Stage 1 first, then study definitions -> type the term. Goal: 90% twice plus the separate application checks. Evolution slides 3-37 and Diversity slides 4-21.

Phylogeny

The evolutionary history and branching relationships of organisms inferred through common ancestry.

Primitive trait

An ancestral trait retained in a focal group and also found in more distantly related groups; not a measure of inferiority.

Derived trait

A newly evolved trait relative to the ancestral condition of the lineage or clade being compared.

Parallel evolution

Independent evolution of similar changes through modification of the same ancestral structures or mechanisms in different lineages; course example: independent loss of functional GULO.

Charles Darwin

Naturalist who developed evolution by natural selection: heritable variation affects survival and reproduction, changing populations over generations.

Natural selection

Differential survival and reproduction associated with heritable trait variation, causing those variants to change in frequency across generations.

Stabilizing selection

Selection favoring intermediate trait values over either extreme.

Artificial selection

Evolutionary change caused by humans preferentially breeding organisms with desired heritable traits.

Convergent evolution

Independent evolution of similar adaptations in different lineages, without the similarity being inherited from their recent common ancestor.

Modern Synthesis

Integration of Darwinian natural selection with Mendelian genetics and population genetics to explain evolutionary change.

Mutation

A change in DNA sequence that can create a new allele; it is not directed by an organism's needs.

Gene flow

Transfer of alleles between populations through movement and successful reproduction.

Genetic drift

Change in allele frequencies due to chance sampling rather than fitness differences; especially strong in small populations.

Genetic bottleneck

A sharp reduction in an existing population that leaves a small, potentially unrepresentative sample of its former genetic variation.

Founder effect

Genetic drift when a small set of individuals establishes a new population with an unrepresentative sample of source-population alleles.

Heritability

The proportion of phenotypic variation associated with genetic variation in a specified population and environment; not the genetic percentage of one individual.

Monogenic trait

A trait whose variation is primarily associated with a single gene.

Polygenic trait

A trait influenced by variation at multiple genes, often producing continuous variation together with environmental influences.